dhewm3/neo/sys/linux/setup/lokisetup/xsu.diff

--- loki_setup/CHANGES	2004-11-20 07:43:42.000000000 -0600
+++ loki_setup.zinx/CHANGES	2005-03-16 16:56:46.400205504 -0600
@@ -1,4 +1,6 @@
 Current:
+Christopher Lais (Id Software) - Wed Mar 16 08:09:59 CST 2005
+ * Fix handling of invalid password in xsu
 Ryan C. Gordon (icculus.org) - Sat Nov 20 08:42:16 EST 2004
  * Minor carbon_ui tweaks and corrections to update function.
 Ludwig Nussel - Wed Nov 10 14:21:21 PST 2004
--- loki_setup/xsu.c	2003-07-02 14:40:39.000000000 -0500
+++ loki_setup.zinx/xsu.c	2005-03-16 16:36:17.752988272 -0600
@@ -37,6 +37,7 @@
 #include "xsu.h"
 
 static int term = -1;
+static int term_status = 0;
 
 static gint
 exec_su_failed (gpointer user_data)
@@ -79,22 +80,25 @@
   if ( sig == SIGCHLD && term > 0 ) {
     int status;
     pid_t pid = wait(&status);
+
+    close(term); term = -1;
+    term_status = status;
+
     if ( WIFEXITED(status) ) {
 #ifdef DEBUG
       fprintf(stderr,"Child %d returned\n", pid);
 #endif
-      gtk_exit(WEXITSTATUS(status));
+      /* This is handled at the end of xsu_process */
+      return;
     } else if ( WIFSIGNALED(status) ) { 
 #ifdef DEBUG
       fprintf(stderr,"Xsu: subprocess %d has died from signal %d\n", pid, WTERMSIG(status));
 #endif
       gtk_exit(EXIT_ERROR);
+    } else {
+      fprintf(stderr, "Xsu: got SIGCHLD from %d for unknown reason (%08x)\n", pid, status);
+      gtk_exit(EXIT_ERROR);
     }
-    close(term); term = -1;
-
-    while (gtk_events_pending ())
-      gtk_main_iteration ();
-    gtk_main_quit ();
   }
 }
 
@@ -135,22 +139,27 @@
 	gchar *buffer;
 	char *argv[6], c;
 	fd_set fds;
-	struct timeval delay = { 0, 10*1000 }; /* 10 ms wait */
+	struct timeval delay;
 
 #ifdef DEBUG
     printf("void xsu_perform()\n");
 #endif
 
+	gtk_widget_hide (gtk_xsu_window);
+
+	if (password == NULL)
+		return;
+
 /* 0.2.1 *
 	Minor security fix. Password would remain in memory if we don't
 	clean the password textbox.
 */
-	gtk_entry_set_text(GTK_ENTRY(gtk_password_textbox),"");
-	gtk_widget_hide (gtk_xsu_window);
-	
-	if (password == NULL)
-		return;
+	password_return = g_strdup_printf ("%s\n", password);
 
+	/* Technically, we aren't supposed to modify this, but it should
+	   usually be OK because we're explicitly clearing it afterwards. */
+	memset (password, 0, strlen (password));
+	gtk_entry_set_text(GTK_ENTRY(gtk_password_textbox),"");
 
 /* xsu 0.2.1 *
 	Option to set the DISPLAY environment
@@ -177,6 +186,9 @@
 	argv[2] = "-c";
 	argv[3] = buffer;
 	argv[4] = NULL;
+#ifdef DEBUG
+	fprintf(stderr, "%s %s -c %s\n", su_command, username, buffer);
+#endif
 	term = exec_program(su_command, argv);
 	/* We are not a gnome-application anymore but under control of su */
 
@@ -231,33 +243,65 @@
 	fprintf(stderr, "Got it!\n");
 #endif
 
-	/* Discard any remaining characters on stdin */
-	for(;;) {
+	/* Slurp up any extra characters immediately after the password prompt,
+	   because su might clear the buffer after we send the password if we
+	   don't. */
+	for (;;) {
 		FD_ZERO(&fds);
 		FD_SET(term, &fds);
-		if ( select(term+1, &fds, NULL, NULL, &delay) ) {
-		    if ( read(term, &c, 1) <= 0 )
-			break;
+
+		delay.tv_sec = 0;
+		delay.tv_usec = 10*1000; /* 10 ms wait */
+
+		if (select(term+1, &fds, NULL, NULL, &delay) > 0) {
+			if (read(term, &c, 1) < 0)
+				break;
 		} else
 			break;
 	}
 
-	password_return = g_strdup_printf ("%s\n", password);
 #ifdef DEBUG
  	fprintf(stderr,"Sending password\n");
 #endif
 /* 0.2.2 *
 	Minor security fix, clear the password from memory
 */  
-	memset (password, 0, strlen (password));	
 	if ( write(term, password_return, strlen(password_return)) < 0 ) {
 	    perror("write");
 	}
+
 	memset (password_return, 0, strlen (password_return));
 	g_free (password_return); password_return = NULL;
-	g_free (password); password = NULL;
 
-	//gtk_main();
+	/* Eat up any output, and wait for a SIGCHLD saying su exited */
+	while (term >= 0) {
+		FD_ZERO(&fds);
+		FD_SET(term, &fds);
+
+		delay.tv_sec = 0;
+		delay.tv_usec = 10*1000; /* 10 ms wait */
+
+		if ( select(term+1, &fds, NULL, NULL, &delay) > 0 ) {
+		    read(term, &c, 1);
+#ifdef DEBUG
+		    fprintf(stderr, "read from pty: %02x\n", c);
+#endif
+		}
+
+		while (gtk_events_pending ()) 
+		  gtk_main_iteration ();
+	}
+
+	if (WIFEXITED(term_status) && WEXITSTATUS(term_status)) {
+		/* su failed, so ask for the password again */
+#ifdef DEBUG
+		fprintf(stderr, "returning control to gtk\n");
+#endif
+		gtk_widget_show (gtk_xsu_window);
+	} else {
+		/* Exit normally */
+		gtk_main_quit();
+	}
 }